Chapters Transcript Foot Deformities in Cerebral Palsy Course: NYU Langone Orthopedics Webinar - Pediatric Foot Deformities: From Common to Complex So we're gonna switch gears a little bit here, and I think you'll find that there's some common themes with things we've already discussed. Um, obviously we're gonna discuss deformities that have already been talked about, but in a very different context, and that's the context of children that have cerebral palsy. Um, as many of you know, some of the concepts in CPE because it's better studied than some of these more rare conditions, um, will can be extrapolated to other things, but we're really gonna be focused just on CPA and this talk. So we'll try to get through in the allotted time. Sorry guys, I have nothing to disclose. OK. So CP, as everyone on the call knows, most common motor disability in childhood, and it's the result of an injury to the brain that occurs less than 2 years old. So your 5 year old child with a near drowning can be considered to have a CP-like condition but not strictly CP. So we do try to keep with that under 2 year old time frame when we talk about CP. And the incidence in the US has essentially stayed the same for several years. It's estimated to be between 1.5 to 2.5 for 1000 live births in the US, and foot deformities are remarkably common in up to 80% of children with CP. Typically we use something called the GMFCS classification, which I'm sure is well known to everyone on the call. You've probably all seen various graphics like this before, but it's essentially a way of communicating from level 1 to level 5 in terms of ambulation and function. So our level 1 through 3s being our ambulatory children and our 4s and 5s being children that are primarily non-ambulatory, and that's a really good context to think about treatment protocols for these patients, because the goals are going to be very different depending on whether they ambulate or they do not. The natural history of foot deformity in CP, much like foot deformity in general, and I think Doctor Brant alluded to this, is that you really don't know when the child is quite little what the foot deformity may be. In CP the foot deformity um ultimately may not be apparent until age 7 to 8. So the overall tone and the anatomic classification, meaning quadriplegic, is it unilateral or hemiplegic, is it bilateral or diplegic, that's gonna help determine the most common deformities and also the treatment. Um, in ambulatory children, this deformity is going to limit gait efficiency. In non-ambulatory children, the deformity is going to prevent comfortable shoe wear as well as orthotic wear. And so there are many deformities, and they get quite complex, but I wanted to touch on the three most common that we see, and that's Aquinas, caboveras, and Plano valgus. So I'm hoping to give you a little bit of an algorithm and a framework within which to see these three deformities, because it gets very complex and very quickly as we'll see. So let's start with equinnas. This is the most common foot deformity that we see in CP, um, and initially treated with uh physical therapy, uh, plantar flexion controlling orthotics, which we'll hear about from uh Jessica Hubert in our next talk, as well as uh the consideration of something called serial casting. Um, which is a way to cast out or give a little more motion for those kids, especially the very little ones who do have a bit of a quina contracture and for various reasons may not be operative candidates. Um, just as an aside, and I'm sure Jessica will allude to this, you really want to make sure uh that They have knee immobilizers as well. Uh, and that also helps to get a stretch through both the gastroc and the soleus while they're undergoing casting. And then finally, surgical management. So this is really only an option, um, in the older children or in young children where orthotic wear has become challenging, where they have increased contracture to the point that non-operative measures are ineffective, um, or midfoot break. Um, and as Dr. Brant alluded to in his talk, you really want to be careful during the physical examination. To really get the calcaneus and neutral, or else you are going to think you have much more dorsiflexion than you actually do, and this is something that we teach our residents. So in thinking about what surgical releases to do, so you say, OK, this kid has failed everything, we, I believe they need a surgical procedure. Your physical exam is really going to determine your zone of surgical release. So we talked about the silver skill testing in Doctor Brant's lecture, and this is really paramount to see whether or not an Achilles lengthening um would be advised versus a gastrocnemius, uh. Release. And so this is very important because if only the gastrocnemius is tight and you do an Achilles lengthening, you could see how that would be very problematic. It can lead to over lengthening, um, and so because over lengthening is so bad, it is not really fixable surgically, um, and can lead to a very profound crouch gait pattern. Many surgeons who treat children with cerebral palsy were err on the side of treating gastrocnemias and not doing an Achilles lengthening if possible. The best paper looking at this is one by Ben Shore that now I can't believe it is almost 15 years old, I'm looking at a systematic review of surgical correction of equinnas in children with cerebral palsy. Um, and they showed that children under 8 who have an Achilles lengthening will have a very high rate of recurrence, and that over lengthening is quite common and so you should always err on the side of making them a bit tighter as opposed to a little bit looser. Um, in fact, it's so difficult for people to come to consensus that they actually performed a Delphi consensus study looking at indications for gastroc soleus lengthening. So this is a procedure that in the past had been done all the time, very routinely. We still do it often, but now our indications are much more conservative. Um, there's some very smart people on this paper. I would encourage you to read it if you treat these patients. I mean, it really gives very good tips on how not great the literature is and so expert consensus on what should be done is really critical. So we talk about procedure choice, we talk about zone one, which is address uh addressing the gastrocnemius only. Um this is preferred in younger patients and then diaplegic patients to avoid overcorrection, and zone 3, or tend to Achilles lengthening is preferred in hemiplegics, who can have a more severe contracture and obviously more asymmetry, and those with very severe contracture. So the take home points are to maximize non-operative management. Um, increased recurrence of index surgery less than 8, increased incidence of over lengthening and diplegics, and to err on the slightly tighter side. Let's move on to Veris. We heard an excellent talk from Doctor Latrenta, and this is really common in younger children with CP. This tends to resolve, um, especially in diplegics, and they can drift into valgus by age 7 to 8. And this is why I always caution not to operate too early. They also tend to have an equinous, and so in the young patients, you really want to treat based on the equinnas algorithm that we discussed. But in hemiplegics, it does tend to persist. You want to always maximize your non-operative intervention first, orthotics, PT plus or minus Botox, and consider surgical treatment for increased cholosities, painful orthotic wear really rigid deformity. And so, um, this is a great paper looking at another Delphi technique, as you can see the literature and CP is is a little bit more challenging than it is in other neurotypical pathologies looking at assessment of foot alignment and function. And preoperative planning is really paramount. You want to make sure you conduct a thorough physical exam, considering all parts of the foot. You will do an observational gait analysis, which sounds fancy, but it really just means that you are watching that kid walk, both in the frontal and sagittal plane in your clinic. If you want to take a video of this, you certainly can to save it in the chart. For those who are lucky enough to have instrumental. analysis with EMG. This is actually where it can be really helpful to instrument the tibialis anterior and tibialis posterior, because they can both be involved with the child's spasticity and tone. It can give you some sense as to what you really would consider transferring. Another good hack, if you do not have instrumented gait analysis, is to have your spasticity team perform Botox preoperatively into the tendon you are considering transferring, i.e., if a child has varus and you believe based on your exam and observational gait analysis, the tibialis posterior is the one that is the most affected, you can have your spasticity team or if you do it yourself, you can do it, um, inject into the tibialis posterior muscle and see if this gives you the desired effect. Um, and there are, this is a very good algorithm from that same paper about classification of the foot deformity that can lead to the soft tissue and balance. So if they do not have a rigid deformity, you really want to focus on tendon transfers. And the workhorse procedure, but there are many techniques, um, if tip post is involved in something called the split posterior tibialis transfer, um. Many people will move half of tip post laterally onto Perroneous brevis. There are a ton of different ways to do this. Some people bury it in bones, some people put it in the cuboid. It's a lot of different ways, but really the key to this procedure is that you have balance and equal tension on both the medial and lateral limbs. Whatever works best in your hands is completely fine. The key is you must balance it, and the foot should remain balanced and neutral. So split posterior tibial transfer is the best option in the right patient. Kids over 8 who have a diagnosis of CP. Who have flexible virus. Flexible is really key for tendon transfers. No other fixed deformity, and if you have it, EMG analysis showing posterior tibiallysis is working out of phase. So does a specific tendon transfer even matter for these? And the answer is no. So when I talked about that you can do, I put it into perineus brevis, but you can do whatever you like, and that's because there is a study looking at long term follow up of quinovious foot in kids with CP showing that the determinants of good outcome, like we talked about, the foot has to be balanced. They have to be older, they have to be hemiplegic, the diplegics do not as well, and kids who amulated beforehand. So no matter what you do, you must get it balanced. That is the key, the right procedure and the right patient. So take home points for varis. More common in hemiplegics, up to 31% will develop virus, can also be seen in non-ambulatory diplegics. Thorough physical exam is key. You must take into account every deformity and treat it. And there are many procedures that are described for this, all have kind of variable results, and it's probably because we haven't totally figured out the exact procedure that is right for the exact patient. So we're going to talk about Plano valgus, we had excellent talk about this. In CP it's mostly due to muscle imbalances of the gastroc and the peroneus brevis, causing that hind foot valgus. They can also have a tibial torsion or femoral anteversion that can also contribute, and they tend to also have weakness and poor motor control, right? All of this takes an effect. And so what you begin to see is that weight bearing on the medial column and a mid-foot break. And with puberty and with weight gain, they can get further collapse that's quite profound. So the natural history is as was talked about even in neurotypical kids, and kids under age 5, it's very unpredictable. You are not intervening. Um, if it's unilateral, it may resolve, it may go into a quinovirus as they get older. Bilateral can remain stable and flexible, but it can also stiffen significantly in adolescence. So the evaluation is really important here, cause your treatment's gonna depend on the age, flexibility, and the tone pattern. Is it flexible? Are they strong? Are they spastic, and do they have good motor control? So there's a lot of factors here, and this is when you really need to be multidisciplinary. If you're lucky enough to have a spasticity team, a good neurologist or physiatrist with whom you work, that is critical to appropriately evaluating these kids. And radiographs. If you say, hm, this looks like a lot of valgus, those are kids that should get X-rays. Doctor Brant talked about this expertly earlier, but you want to take a look at um the talocalcaneal angle, what kind of taillonavicular coverage they have, and also looking at the tail of first metatarsal angle. So in terms of treatment, if it's flexible, if it's mild, you can brace them, you can do shoe modifications. Some of these children as they get older, don't really want to wear braces, and some of them don't have to, so that's OK. You have to work with the patient. But certainly if there's skin breakdown, if there's any pain, you do want to consider a surgical procedure. As you can see by the number of procedures lifted uh listed, there's really no consensus in CP about what to do. Seems like the children who do the best are when you have considered every single deformity that they have. So you have to treat the hindfoot valgus, the midfoot break, as well as the supination deformity in concert altogether, and there are various ways to do that. So another question we get into often is, do you do an osteotomy or do you do a fusion. Fusion is a very scary word, right? Um, parents hear that and they say, oh, put your two bones together. It can sound very scary. So there's an excellent paper which I would encourage you all, um, to. Download looking at long term outcomes of Plano valgus foot correction in children with CP. And they looked at, you know, an age matched control of the osteotomy and the fusion patients. There's a big variety in CP but they tried to get to the bottom of it and match it as much as, as well as they could. And they found clinically acceptable outcomes in both groups. They were improved peder barografts in both groups, but 21% required revision surgery for midfoot collapse, regardless of whether they had an osteotomy or a fusion. So that's something to tell parents. The overall disease does not change just because you are making their foot look good. So if their spasticity is not treated, or if there are other untreated underlying issues, those will continue to persist despite the fact that the foot looks amazing during surgery. And again, this is gonna sound familiar, balancing the foot decreases recurrence. So having that overall balance, however you choose to do that is really paramount. So take home points for Plano valgus. No treatment in kids under 5. Many will remain flexible. Orthotics can be helpful if the deformity is flexible. Thorough physical exam is paramount. Consider all the deformities, what's fixed, what is not, and the contribution of the tibialis anterior versus posterior. There are many prescribed procedures that are described in the literature. All have shown fairly high revision rates. So the most important thing is balance. Here are my references. Thanks very much. Published November 20, 2024 Created by Related Presenters Mara Karamitopoulos, MD View full profile
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